绘制广场上存在的位图图像

Question

我有一个位图图像，我想绘制一个方形在这个图像的特殊位置，我研究了但我找不到任何解决方案，所有的解决方案都是为了在空视图上创建广场，请告知我是初学者

public class DrawView extends View 
{ 
    Paint paint = new Paint(); 

    public DrawView(Context context) 
    { 
     super(context); 
    } 


    @Override 
    public void onDraw(Canvas canvas) 
    { 


     Paint myPaint = new Paint(); 
     myPaint.setColor(Color.WHITE); 
     myPaint.setStyle(Paint.Style.STROKE); 
     myPaint.setStrokeWidth(2); 
     canvas.drawRect(10, 10, 100, 100, myPaint); 


    } 

} 

我应该将我的位图图像转换为convas？怎么样？

Answer 1

试试这个，这你想要做什么和一些：

import android.content.Context; 
import android.graphics.Canvas; 
import android.graphics.Color; 
import android.graphics.Paint; 
import android.view.View; 

public class DrawView extends View { 
    Paint paint = new Paint(); 

    public DrawView(Context context) { 
     super(context);    
    } 

    @Override 
    public void onDraw(Canvas canvas) { 
     paint.setColor(Color.BLACK); 
     paint.setStrokeWidth(3); 
     canvas.drawRect(30, 30, 80, 80, paint); 
     paint.setStrokeWidth(0); 
     paint.setColor(Color.CYAN); 
     canvas.drawRect(33, 60, 77, 77, paint); 
     paint.setColor(Color.YELLOW); 
     canvas.drawRect(33, 33, 77, 60, paint); 

    } 

} 

要绘制它： 进口android.app.Activity; import android.graphics.Color; import android.os.Bundle;

public class StartDraw extends Activity { 
    DrawView drawView; 

    @Override 
    public void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 

     drawView = new DrawView(this); 
     drawView.setBackgroundColor(Color.WHITE); 
     setContentView(drawView); 

    } 
} 

来源：Android canvas draw rectangle